And if you are talking about ecosystem around each language. Consider that C++ have thousands of ready-to-use libraries. How many of them have US ? Yeah. It will be much easier to integrate them (say you need XML praser no problem!), just add headers and you good to go.
C++ is not hard languge. By no means. Unless you need to do very low level things. I don't think learning enough to code gameplay will hell lot of task. And hurders thousands of existing C++ will welcome change.
Yeah I know what are you talking about. I think there are diffrent reasons rather than using C++ for gameplay. More important is lack of proper documentation of code, and more important default sample provided also do not have any documentation and it;s wrote in very, very bad manner (I'm not purist but I like when code self-document at least).
Also other factors count. But since we talking about programming they do not belong here.